Your Ml 320 stalls at 75-78 degrees centigrade coolant temperature Will ot restart until itn cools down to 40 degrees centigrade What are the probable causes?

Answer 1

We have seen this and found it to be the crank sensor At Fault and sometimes the cam sensor. What happens is the sensor is a series of windings and they open or even gain high resistance as they heat up then when they cool down the resistance drops and they work fine the idea is measure the resistance of the sensors cold and when the vehicle stope check the resistance again and I'll bet you will find that the value from hot to cold will be different. The own where the resistance is much higher will be the one at fault. good luck

Also to add. In most cases this is attributed to the hard start when warm. Or long crank times during a warm engine. Yet when cold the engine will start up right away always. Almost always this is in reference to the CPS sensor. or crank shaft position sensor. Easily bought on eBay for less then 50 dollars. It is not as easily changed. But the best way I have to change this sensor was to remove the left front tire, and then the plastic wheel well housing. It only has about 5 screws. The sensor is located by the firewall, left side(driver side). And down low near where the trnasmission mates to the engine block. It has a 2 wire pigtail.